Filter device for fluids

ABSTRACT

A filter device for fluids, having a connection member ( 1 ) with a fluid input ( 19 ) for unfiltrate and fluid output ( 13 ) for filtrate, having a first ( 43 ) and a second filter element ( 3 ) and having a switching device ( 29 ) located in the connection member ( 1 ), by means of which a fluid connection between the fluid input ( 19 ) and fluid output ( 13 ) can be selectively established via the first ( 43 ) or via the second filter element ( 3 ), is characterized in that one of the filter elements is integrated into the interior of the connection member ( 1 ) as an auxiliary filter ( 43 ).

The invention relates to a filter device for fluids, having a connection member with a fluid input for unfiltrate and fluid output for filtrate, having a first and a second filter element and having a switching device located in the connection member, by means of which a fluid connection between the fluid input and fluid output can be selectively established via the first or via the second filter element.

Filter devices of this type are prior art. As so-called “double filters”, such filter devices are used, inter alia, in transmissions, such as stationary transmissions or ship transmissions, as oil filters. In such installations, which are to be operable without operational interruptions, these filter devices enable the replacement of a used filter element to be performed without shutting down the affected facility or doing without a filter function during the maintenance measures.

Proceeding from this prior art, the invention has the object of providing a filter device of the type in question, which is distinguished by simple operability and a particularly compact construction.

This object is achieved according to the invention by a filter device which has the features of Patent claim 1 in its entirety.

Accordingly, the filter device according to the invention is distinguished in that a filter element of the filter device is integrated in the interior of the connection member as an auxiliary filter. While in the prior art, two filter elements are provided on the exterior of the connection member, which are each designed and dimensioned for a filter performance corresponding to the full operating duration of the respective filter element, in the device according to the invention, only one correspondingly large-dimensioned filter, which is removably attached on the exterior of the connection housing, is necessary, because the device is further operable via the inner auxiliary filter during the replacement of this outer filter. Since the further operation via the auxiliary filter, which is referred to here as the first filter element, only occurs during the short phases of the replacement of the removable filter, which is referred to here as the second filter element, a small-dimensioned auxiliary filter, which is easily integratable in the design of the connection member, is usable as an auxiliary filter.

As in the prior art, the second filter element, as the main filter, can be removably attached to the exterior of the connection member and can be implemented in the form of a so-called spin-on cartridge, for example.

In particularly advantageous exemplary embodiments, the switching device has a ball valve.

In a particularly advantageous manner, the auxiliary filter and ball valve can be unified in the connection member to form one assembly, which enables a particularly compact construction of the connection member.

In particularly advantageous embodiments, the assembly is configured in this regard so that auxiliary filter and ball valve have a functional element shared thereby or functional elements pressing directly against one another, so that ball valve and auxiliary filter practically form a module.

In this case, the arrangement can advantageously be made so that a spacer member, which holds the switching ball of the ball valve in position in the ball valve housing, has an input opening, as a shared functional element of auxiliary body and ball valve, which forms a fluid path between them and the inner filter cavity of the auxiliary filter.

In particularly advantageous exemplary embodiments, the ball valve housing is extended beyond the switching ball along an axis, which extends through the filter cavity of the auxiliary filter, wherein an output channel, which extends perpendicularly to the main axis and leads to the fluid output, branches off thereon from the ball valve housing. The auxiliary filter is thus practically directly installed in the output channel, so that the auxiliary filter arranged on the branching point of the output channel in the ball valve housing has a direct fluid connection on the exterior of its filter medium, which encloses the inner filter cavity, to the output channel.

In a particularly advantageous manner, the ball valve housing can have, on the side opposite to the input opening of the auxiliary filter, an entry opening enclosing the main axis, which has a fluid connection to the unfiltered side of the respective main filter attached to the connection member, and can also have an inflow opening, which is aligned on the spindle axis of the ball valve, which is perpendicular to the main axis, and has a fluid connection to the fluid input, wherein the inflow opening is selectively connectable, by the switching ball, to the entry opening leading to the main filter or to the input opening leading to the auxiliary filter. The invention is described in detail hereafter on the basis of an exemplary embodiment illustrated in the drawing. In the figures:

FIG. 1 shows a perspective diagonal view, which is drawn in only a slightly smaller scale in relation to a natural embodiment, of an exemplary embodiment of the filter device according to the invention, wherein a main filter is omitted;

FIG. 2 shows a longitudinal section of the exemplary embodiment in the scale of FIG. 1, wherein a main filter is shown, and

FIG. 3 shows a sectional illustration corresponding to section line III-III of FIG. 2.

FIG. 1 shows the exemplary embodiment to be described here of the filter device according to the invention without a main filter attached to the connection member 1. The main filter is identified in FIG. 2 with 3. The main filter 3 is a so-called spin-on filter cartridge, which is removably connectable by a screw connection in the typical manner in the case of such filter cartridges on a filter head 5 implemented on the connection member 1. A fluid guide 7, which forms an input to the unfiltered side of the main filter 3, and a central fluid guide 9, which forms the output from the filtered side 6 of the main filter 3, are provided on the filter head 5. This fluid guide 9 is formed by a channel, which opens in the connection member 1, with regard to the illustration of FIG. 2, in the vertical direction on top in an output channel 11 extending perpendicularly to the vertical, which ends at a fluid output 13 of the connection member 1. A spring-loaded check valve 15, which releases the flow path when filtrate flows via the fluid guide 9 into the output channel 11 during filtration operation of the main filter 3, but closes the fluid guide 9 when the main filter 3 is removed, is located at the discharge of the fluid guide 9 into the output channel 11. In the illustration of the drawing corresponding to FIG. 2, an input channel 17 extending parallel thereto is located below the output channel 11 in the connection member 1, this input channel, starting from the fluid input 19 of the connection member 1, merging into a bulge 21, which continues the fluid path, around the wall of the fluid guide 9, into an input chamber 23, see FIG. 3. This input chamber 23 is located on a ball valve housing 25 at an inflow opening 27 of a ball valve 29. More precisely, the inflow opening 27 is aligned with the spindle axis 31 of the rotatable switching ball 33 of the ball valve 29.

The ball valve housing 25 extends along a main axis 35, which extends vertically in FIG. 2. For its axial position along the main axis 35, the switching ball 33 is held between sealing disks 37, of which the lower one in the drawing presses against a housing projection 39 of the ball valve housing 25. The upper sealing disk 37 is held on a spacer member 41, which is a component of an auxiliary filter 43. More precisely, the spacer member 41 forms the element receptacle for the filter element of the auxiliary filter 43. As the unfiltered side, this has an inner filter cavity 45, which has a fluid connection to the ball valve 29, via an input opening 47 located in the spacer member 41, which is implemented concentrically to the main axis 35 in the spacer member 41. The auxiliary filter 43 has a filter medium enclosing the filter cavity 45, which is arranged in the present exemplary embodiment between two fluid-permeable support pipes 48 and 49, which extend between filter end members 51 and 53, of which the lower end member 51 in the drawing presses against the spacer member 41 used as the element receptacle. In this case, the end member 51, which forms the base part of the filter element, and the spacer member 41 can be one component. The entire assembly made of the ball valve 29 and auxiliary filter 43 is positioned by means of a screw-in lid 55 in the ball valve housing 25 via the upper end member 53 and the support pipes 48, 49.

In the drawings, the ball valve 29 is shown in a switching position which corresponds to the filtration operation using the main filter 3. In this case, as shown, the switching ball 33 blocks the input opening 47 of the spacer member 41 and therefore the fluid entry to the auxiliary filter 43, so that it is disabled. On the other hand, the switching ball 33, as can be seen most clearly from FIG. 3, establishes the fluid connection between the input chamber 23, and therefore the fluid input 19, and an entry opening 57, which leads via the fluid guide 7 to the unfiltered side 8 of the main filter 3, so that it is in function for filtration operation, wherein the filtrate reaches the output channel 11 via the fluid guide 9 and the check valve 15 and leaves the device via the fluid output 13.

On the other hand, when the ball valve 29 is switched over, in that the switching ball 33 is rotated by means of the hand lever 59, in that the hand lever 59 is pivoted clockwise in the viewing direction corresponding to FIG. 3, the switching ball 33 closes the entry opening 57 and releases the fluid path from the input chamber 23 to the input opening 47 of the auxiliary filter 43. While the main filter 3 is therefore disabled and can be replaced, the operation of the affected facility is possible via the auxiliary filter 43 without interruption. For the operational monitoring during normal filtration operation, a contamination display 61 is provided, which is only visible in FIG. 1, which monitors the differential pressure between input channel 17 and output channel 11. 

1. A filter device for fluids, having a connection member (1) having fluid input (19) for unfiltrate and fluid output (13) for filtrate, having a first (43) and a second filter element (3) and having a switching device (29) located in the connection member (1), by means of which a fluid connection between the fluid input (19) and fluid output (13) can be selectively established via the first (43) or via the second filter element (3), characterized in that one of the filter elements is integrated into the interior of the connection member (1) as an auxiliary filter (43).
 2. The filter device according to claim 1, characterized in that the second filter is removably attached as a main filter (3) on the exterior of the connection member (1).
 3. The filter device according to claim 1, characterized in that the switching device has a ball valve (29).
 4. The filter device according to claim 1, characterized in that auxiliary filter (43) and ball valve (29) are unified to form an assembly in the connection member (1).
 5. The filter device according to claim 1, characterized in that auxiliary filter (43) and ball valve (29) have a functional element (41) shared thereby, or functional elements pressing directly against one another.
 6. The filter device according to claim 1, characterized in that a spacer member (41), which holds the switching ball (33) of the ball valve (29) in the ball valve housing (25), as a shared functional element of auxiliary filter (43) and ball valve (29), has an input opening (47), which forms a fluid path between it and the inner filter cavity (45) of the auxiliary filter (43).
 7. The filter device according to claim 1, characterized in that the ball valve housing (25) is extended beyond the switching ball (33) along a main axis (45), which extends through the filter cavity (45) of the auxiliary filter (43), and an output channel (11), which extends perpendicularly to the main axis (35) and leads to the fluid outlet (13), branches off thereon from the ball valve housing (25).
 8. The filter device according to claim 1, characterized in that the auxiliary filter (43), which is arranged at the branching point of the output channel (11) in the ball valve housing (25), has a filter medium which separates the inner filter cavity (45) from the output channel (11).
 9. The filter device according to claim 1, characterized in that the ball valve housing (25), on the side opposite to the input opening (47) of the auxiliary filter (43), has an entry opening (57), which encloses the main axis (35), and which has a fluid connection to the unfiltered side of the respective main filter (3) attached to the connection member (1), and also an inflow opening (27), which is aligned on the spindle axis (31) of the switching ball (33), which is perpendicular to the main axis (35), and has a fluid connection to the fluid input (19), and the inflow opening (27) can be selectively connected by the switching ball (33) to the entry opening (57) leading to the main filter (3) or to the input opening (47) leading to the auxiliary filter (43). 